Dr. Robert A. Bubeck
Senior Research Scientist and Professor

Robert A. BubeckAreas of Research Interest

  • Polymer Processing – Melt processing thermotropic liquid-crystalline polymers (TLCPs) usually results in the fabrication of molded articles that possess complex states of orientation that vary greatly as a function of thickness and part geometry. This condition gives rise to “skin-core” morphologies and sample anisotropy. In collaboration with Northwestern University, synchrotron-based wide-angle X-ray scattering and near edge x-ray absorption fine structure are being used to characterize the orientation distributions in “skin” and “core” layers in injection-molded parts. Experimental results were compared with the modeling of the processing of TLCPs with ‘polydomain’ simulations based upon Larson-Doi and Folger-Tucker models within the framework of the Moldflow® software package. Other areas of activities have been in the effects of orientation in syndiotactic polystyrene and other thermoplastics.
  • Polymer Toughening – Improvement of polymer properties via added phases and the manipulation of orientation. Recent efforts have addressed the improved processing and toughening of epoxies for use in composite structure wind turbine blades fabricated using vacuum assisted reaction transfer molding processing using nano-scale hyperbranched siloxane polymer particles. Failure analyses and durability factors of polymeric systems in engineering applications are additional areas of attention.  
  • Synchrotron-Source Materials Characterization – Through the use of national facilities such as the Advanced Photon Source at Argonne and the National Synchrotron Light source at Brookhaven, soft X-ray based near-edge X-ray absorption fine structure (NEXAFS) and in-situ X-ray scattering techniques have been used to characterize dendrimer nano-composites, high performance films (PIBO), Xylon fiber processing, and orientation distributions in liquid crystalline polymers. Fourier-Transform Infrared – Attenuated Total Reflectance (FTIR-ATR) is an additional spectroscopy tool utilized in conjunction with the synchrotron-based techniques.

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Education

B. S.  Drexel University, Philadelphia, PA (1970, Metallurgical Engineering)

M.S.  Cornell University, Ithaca, NY (1972, Materials Science and Engineering)

Ph. D. Cornell University, Ithaca, NY (1976, Materials Science and Engineering)

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Research Experience

  • Michigan Molecular Institute, Midland, MI, Senior Research Scientist and Professor in Polymer Science, 2001 to present
  • The Dow Chemical Company, Midland, MI

(1995-98) Technical Leader of the Materials Research Discipline; Project Manager of the Dow Synchrotron Program within the Surface/Microscopy/X-ray Discipline; Development research in liquid crystalline, semi-crystalline and other ordered polymers (Polyethylene Terephthalate, Nanocomposites, Polylactic Acid) (1978-95) Development of engineering thermoplastics with improved durability, including HIPS, ABS, polycarbonates, and syndiotactic polystyrene; Processing, product development and fundamentals of liquid crystalline polymers (Polybenzoxazole), semi-crystalline (Polyethylene), and ordered polymers; Pioneered within Dow synchrotron X-ray scattering and neutron scattering techniques for the in situ characterization of polymers and polymer processing (1976-78) Development of new styrenic thermoplastics


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Additional Expertise & Activities

  • Assembled and taught numerous internal Dow courses on the topics of fracture mechanics, polymer durability, impact toughening of polymers, and blends
  • Failure analysis and many of the key analytical tools required to perform these analyses
  • Surface science including synchrotron-based NEXAFS (near-edge X-ray absorption fine structure) of polymer surfaces

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Patents

    1.  R. A. Bubeck, and C. B. Arends, "Impact Styrene Polymer", U. S. Pat. No. 4, 521,569, June 6, 1985.
    2. R. A. Bubeck, R. B. Clipper, and D. E. Henton, "ABS Compositions Having Trimodal Rubber Particle Distributions", U. S. Pat. No. 4,874,815, October 17, 1989.
    3. R. A. Bubeck, S. J. Nolan, C. C. Chau, S. Rosenberg, M. D. Newsham, and M. Serrano, "Polybenzazole Fiber with Ultra-High Physical Properties", U. S. Pat. No. 5,286,833, February 15, 1994.
    4. R. A. Bubeck, C. C. Chau, S. J. Nolan, S. Rosenberg, M. D. Newsham, and M. Serrano, "Polybenzazole Fiber with Ultra-High Physical Properties and Method for Making Them", U. S. Pat. No. 5,356,584, October 18, 1994.

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Scientific and Professional Societies

  • American Physical Society (APS) - Fellow
  • American Chemical Society (ACS) – Member for over 30 years
  • Materials Research Society
  • Advisory Board of Macromolecular Science - Physics
  • Co-organized the APS-DHPP symposium on "Industrial Research in Polymer Physics: Challenges and Opportunities", March 20-24, 1995
  • Cornell High Energy Synchrotron Source Users' Executive Steering Committee (1991 - 95), Chairman, 1993 and 1994
  • Advanced Photon Source Users’ Organization Steering Committee, elected to a three- year term, 1995 - 1998
  • Co-organized the "Industrial R&D with Synchrotron Radiation" workshop at the 9th APS Users' Meeting, October 15, 1998
  • Chaired the Dow Chemical Spring Science and Technology Meeting, 1998
  • Member of the Tau Beta Pi, Alpha Sigma Mu, Sigma Xi academic fraternities

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Publications

Selected Recent Publications

    1. R. A. Bubeck, “Structure-Property Relationships in Metallocene Polyethylenes”, Materials Science and Engineering Reviews, 2002, R39 1-28 – Invited paper.
    2. P. R. Dvornic, R. A. Bubeck, S. D. Reeves, J. Li, L. W. Hoffman, “Nano-Scale Templating Using Honeycomb-like Poly(amidoamine-organosilicon) (PAMAMOS) Dendrimer Networks”, Silicon Chemistry, 2003, 1.
    3. S. Rendon, W. R. Burghardt, A. New, R. A. Bubeck, and L. S. Thomas, “Effect of Complex Flow Kinematics on the Molecular Orientation Distribution in Injection Molding of Liquid Crystalline Copolyesters”, Polymer, 2004, 45, 5341 – 5352.
    4. R. A. Bubeck, P. R. Dvornic, J. Hu, A. Hexemer, X. Li, S. E. Keinath, and D. A. Fischer, “Near Edge X-ray Absorption Fine Strucutre (NEXAFS) Studies of Copper Ion-Containing PAMAMOS Dendrimer Networks”; Macromolecular Chemistry and Physics, 2005, 206, 1146 – 1153.
    5. R. A. Bubeck, L. S. Thomas, S. Rendon, W. R. Burghardt, A. Hexemer, D. A. Fischer, “Characterization of the Skin Orientation of Thermotropic Liquid-Crystalline Copolyester Moldings with Near-Edge X-Ray Absorption Fine Structure’, Journal of Applied Polymer Science, 2005, 98, 2473.
    6. S. Rendon, R. A. Bubeck, L. S. Thomas, W. R. Burghardt, A. Hexemer, and D. A. Fischer, “Interrogation of “Surface”, “Skin”, and “Core” Orientation in Thermotropic Liquid-Crystalline Copolyester Moldings by Near-Edge X-Ray Absorption Fine Structure and Wide-Angle X-ray Scattering.”  Journal of Applied Polymer Science, 2007, 106, 2502-2514.
    7. J. Fang, W.R. Burghardt and R.A. Bubeck. “Polydomain Model Predictions of Molecular Orientation in Isothermal Channel Flows of Thermotropic Liquid Crystalline Polymers.” Polymer Engineering & Science, 2008, 48, 2258-2269.

Additional Publications

    1. R. A. Bubeck and E. J. Kramer, "Effect of Water Content on Stress Aging of Nylon 6-10", Journal of Applied Physics, 1971, 42, 12, 4631.
    2. R. A. Bubeck, "Kinetics of Craze Nucleation and Growth in Polystyrene", Cornell Materials Science Center Report #2671 (Ph.D. Thesis), September 1976.
    3. E. J. Kramer and R. A. Bubeck, "Kinetics of Solvent Crazes in Glassy Polymers", Journal of Polymer Science, Polymer Physics Ed., 1978, 16, 1195.
    4. R. A. Bubeck, "Kinetics of Environmental Stress Cracking in High Density Polyethylene", Polymer, 1981, 22, 682.
    5. R. A. Bubeck, C. B. Arends, E. L. Hall, and J. B. Vander Sande, "Environmental Stress Cracking in Impact Polystyrene", Polymer Engineering and Science, 1981, 21, 10, 624.
    6. R. A. Bubeck and H. M. Baker, "The Influence of Branch Length in the Deformation and Microstructure of Polyethylene", 1982, Polymer, 23, 1680.
    7. A. M. Donald, E. J. Kramer, and R. A. Bubeck, "The Entanglement Network and Craze Micromechanics in Glassy Polymers", Journal of Polymer Science, Polymer Physics Ed., 1982, 20, 1129.
    8. R. A. Bubeck, S. E. Bales, and H. D. Lee, "Changes in Yield and Deformation of Polycarbonates Caused by Physical Aging", Polymer Engineering and Science, 1984, 24, 10, 1142.
    9. R. A. Bubeck, P. B. Smith, and S. E. Bales, "Molecular Origins of Yield and Deformation Behavior in Polycarbonates" Sixth International Conference on Deformation, Yield and Fracture of Polymers, Cambridge, U.K., Apr. 1985.
    10. H. R. Brown, S. J. Kline, P. J. Mills, E. J. Kramer, and R. A. Bubeck, "Real-Time Small Angle Scattering Studies of the Basic Mechanisms of Fatigue in Polystyrenes" Sixth International Conference on Deformation, Yield and Fracture of Polymers, Cambridge, U. K., Apr., 1985.
    11. B. Hammouda, R. A. Bubeck, and D. F. R. Mildner, "Macromolecular Orientation in Hot Stretched and Injection Molded Polystyrene", 1986, Polymer, 27, 393.
    12. B. Hammouda, D. F. R. Mildner, R. A. Bubeck, and M. T. Malanga, "The Inclination Angle of Nonisotropic Inhomogeneities Determined by SANS",1986,  Journal of Applied Crystallography., 19, 320-323.
    13. R. A. Bubeck, B. Hammouda, and H. Kaiser, "Macromolecular Orientation Associated with Shear Bands in Compressed Polystyrene", Polymer Communications, 1986, 27, 354-356.
    14. H. J. Marton, S. E. Bales, R. A. Bubeck, T. A. Dodds, and D. R. Near, "Polycarbonate Copolymers:  Superior Performance through the Controlled Design of Composition", SPE ANTEC, 32, (1986).
    15. R. A. Bubeck, J. A. Blazy, E. J. Kramer, D. J. Buckley, and H. R. Brown, "Real Time Small Angle X-ray Scattering Measurements of HIPS during Tensile Impact as a Function of Deformation Rate", Polymer Communications, 1986, 27, 357-360.
    16. H. R. Brown, E. J. Kramer, and R. A. Bubeck, "Studies of Craze Fibril Deformation During Fatigue in Polystyrene", Journal of Polymer Science: Part B: Polymer Physics, 1987, 25, 1765 - 1778.
    17. R. A. Bubeck, P. B. Smith, S. E. Bales, "Molecular Origins of Deformation Behavior and Physical Aging in Polycarbonate Copolymers", in Order in the Amorphous 'State' of Polymers, S. E. Keinath, R. L. Miller, and J. K. Rieke, Eds., Penum Publishing Corp., New York, New York, 1986, pp. 347 - 358.
    18. S. A. Schwartz and R. A. Bubeck, "Physical Aging in Thermosets of Differing Degree of Cure - Master Curve Generation and the Relation to Mechanical Properties", Polymer Engineering and Science, 1988, 28, 1 - 5.
    19. R. A. Bubeck, J. A. Blazy, E. J. Kramer, D. J. Buckley, Jr., and H. R. Brown, "Real-Time Small-Angle X-ray Scattering Measurements of HIPS and ABS During Tensile Impact", Materials Research Society Symposia Proceedings, 1987, 79, 293.
    20. H. R. Brown, E. J. Kramer, and R. A. Bubeck, "Small Angle X-ray Scattering Studies of Fatigue in Polystyrene", Materials Research Society Symposia Proceedings, 1987, 79, 277.
    21. P. B. Smith, R. A. Bubeck, and S. E. Bales, "2H NMR Analysis of the Molecular Origin of Thermal Relaxation in Polycarbonates", Macromolecules, 1988, 21, 2058.
    22. H. R. Brown, E. J. Kramer, and R. A. Bubeck, "Effect of Deformation Ratio on Fibril Deformation in Fatigue of Polystyrene", Journal of Materials Science, 1988, 23, 248 - 252.
    23. R. A. Bubeck, "Environmental Stress Cracking" in The Encyclopedia of Polymer Science and Engineering, 2nd ed., 1989, 16, 97 – 106.
    24. R. A. Bubeck, Review of "An Improved Method for the Evaluation of Interfacial Surface Tension in Multicomponent Polymeric Systems by the Embedded Fiber Retraction Technique," Chemtracts, 1990, 1, 6, 377.
    25. D. Bradford, B. Hammouda, R. A. Bubeck, J. R. Schroeder, C. J. Glinka, and P. Thiyagarajan, "Treatment of SANS DATA from Hot-Stretched Polystyrene Chains," Journal of Applied Crystallography, 1990, 23, 1 - 5.
    26. R. A. Bubeck, D. J. Buckley, Jr., E. J. Kramer, H. R. Brown, "Modes of Deformation in Rubber-Modified Thermoplastics During Tensile Impact," 8th International Conference on Deformation, Yield and Fracture of Polymers, Churchill College, Cambridge, UK, (April 8 - 11, 1991) 8, 33.
    27. R. A. Bubeck, D. J. Buckley, Jr., E. J. Kramer, H. R. Brown, "Modes of Deformation in Rubber-Modified Thermoplastics During Tensile Impact," Journal of  Materials  Science, 1991, 26, 6249.
    28. R. A. Bubeck, Review of "Crystal Solvates in the Poly[p-phenylene(benzo[1,2-d:4,5-d']bisthiozole-2,6-diyl)]/Poly(phosphoric acid)/Water System," 1991, Chemtracts , 2, 2, 124.
    29. J. R. Schroeder, B. Hammouda, R. A. Bubeck, and J. W. Chang, "SANS from Hot-Stretched Polystyrene Revisited," Journal of Polymer  Science: Part B: Polymer Physics, 1991, 29, 1607 - 1612.
    30. E. O. Shaffer II, C. J. Carriere, and R. A. Bubeck, "Relative Molecular Weight Distribuiton of cis-Polybenzoxazole/Poly-phosphoric Acid Rodlike Liquid Crystalline Polymer Solutions from Dilute Solution Rheometry", Journal of Polymer Science: Part B:  Polymer Physics, 1992, 30, 259.
    31. S. J. Nolan, C. F. Broomall, R. A. Bubeck, B. G. Landes, P. R. Rudolf, M. E. Mills, M. J. Radler, "In-Situ Synchrotron X-ray Scattering Studies of Polybenoxazole Fiber Spinning", Materials Research Society Symposia Proceedings, 1993, 305, 111 - 116.
    32. M. J. Radler, B. G. Landes, S. J. Nolan, C. F. Broomall, T. C. Chritz, P. R. Rudolf, M. E. Mills, and R. A. Bubeck, “In-situ X-ray Scattering Studies of Lyotropic Liquid Crystalline PBO and PBZT Monofilament Drawing", Journal of Polymer Science: Part B: Polymer Physics, 1994, 32, 2573.
    33. S. J. Nolan, C. F. Broomall, R. A. Bubeck, M. J. Radler, and B. G. Landes, "A Monofilament Drawing Device for In-situ Scattering Studies of Orientation Development in Polymeric Fibers”, The Review of Scientific Instruments., 1995, 66, 3, 2652 – 2657.
    34. J. K. Gillie, M. D. Newsham, A. Sen, and R. A. Bubeck, "Coagulation of Poly(p-pheylene benzobisoxazole) in Polyphosphoric Acid Using Aqueous and Nonaqueous Solutions", J. of Polym. Sci.: Part B: Polymer Physics, 33, 1621-1626 (1995).
    35. D. E. Henton and R. A. Bubeck, "The Manufacture and Physical Properties of Rubber-Toughened Styrenics", in Polymer Toughening, C. B. Arends, ed., Marcel Dekker, Inc. (1996)
    36. S. Wu, R. A. Bubeck, and C. J. Carriere, “The Effect of Processing Conditions on the Fracture Behavior of Syndiotactic Polystyrene”, Journal of Applied Polymer Science, 1996, 62, 1483-1490.
    37. R. A. Bubeck, S. R. Bare, B. M. DeKoven, M. D. Heaney, and P. R. Rudolf, "Synchrotron Radiation-Based Research at the Dow Chemical Company" in Industrial Uses of Synchrotron Radiation, ed. L. Terminello, Plenum, 33, 1621 (1996).
    38. J. Beckman, G. B. McKenna, B. G. Landes, D. H. Bank, and R. A. Bubeck, “Physical Aging Kinetics of Syndiotactic Polystyrene as Determined from Creep Behavior”, Polymer Engineering and Science, 1997, 37, 9, 1459- 1468 – SPE Best Paper Award ANTEC 94.
    39. J. D .Barnes, G. B. McKenna, B. G. Landes, R. A. Bubeck, and D. Bank, “Morphology of Syndiotactic Polystyrene as Examined by Small-Angle X-ray Scattering”, 1997, Polymer Engineering and Science, 1997, 37, 9, 1480-1484.
    40. J. Genzer, E. Sivaniah, E. J. Kramer, J. Wang, H. Körner, M. Xiang, S. Yang, C. K. Ober, K. Char, M. K. Chaudhury, B. M. DeKoven, R. A. Bubeck, D. A. Fischer and S. Sambasivan, “Surfaces of Semifluorinated Block Copolymers Studied Using NEXAFS”, In: Applications of Synchrotron Radiation Techniques to Materials Science IV, S. M. Mini; D. L. Perry; S. R. Stock; L. J. Terminello (Eds.), Materials Research Society Symposium Proceedings, 1998, 524, 365-370.
    41. J. Genzer, E. Sivaniah, E. J. Kramer, J. Wang, H. Horner, K. Char, C. K. Ober, B. M. DeKoven, R. A. Bubeck, D. A. Fischer, and S. Sambasivan, “Temperature Dependence of Molecular Orientation on the Surfaces of Semifluorinated Polymer Thin Films”, Langmuir, 2000, 16, 1993-1997.
    42. J. Genzer, E. Sivaniah, E. J. Kramer, J. Wang, H. Horner, M. Xiang, K. Char, C. K. Ober, B. M. Dekoven, R. A. Bubeck, M. K. Chaudhury, S. Sambasivan, and D. A. Fischer, “The Orientation of Semifluorinated Alkanes Attached to Polymers at the Surface of Polymer Films”, Macromolecules, 2000, 33, 1882-1887.
    43. R. A. Bubeck and M. A. Barger, “Injection Blow Molding for Polyethylene Terephthalate”, International Polymer Processing, 2000, XV, 4, 337-341 – Invited paper.
    44. R. A. Bubeck, B. J. Bauer, P. R. Dvornic, M. J. Owen, S. D. Reeves, P. L. Parham, and L. W. Hoffman, Polymeric Materials: Science and Engineering, 2001, 84, 866.
    45. S. Ran, C. Burger, D. Fang, X. Zong, S. Cruz, B. S. Hsiao, B. Chu, R. A. Bubeck, K. Yabuki,, Y. Teramoto, D. C. Martin, M. A. Johnson, and P. M. Cunniff, “In-situ Structural Development During PBO Solution Spinning by Synchrotron WAXS/SAXS Studies”, 2002, Macromolecules, 35, 433-439.
    46. R. A. Bubeck, “Structure-Property Relationships in Metallocene Polyethylenes”, Materials Science and Engineering Reviews, 2002, R39 1-28 – Invited paper.
    47. R. A. Bubeck, L. S. Thomas, W. R. Burghardt, S. Rendon, A. Hexemer, and B. Hart, “Mechanical and Morphological Anisotropy in a Thermotropic Liquid Crystalline Polymer”, 12th Churchill Conference on Deformation, Yield and Fracture of Polymers, 2003, 12, 155-158.
    48. P. R. Dvornic, R. A. Bubeck, S. D. Reeves, J. Li, L. W. Hoffman, “Nano-Scale Templating Using Honeycomb-like Poly(amidoamine-organosilicon) (PAMADOS) Dendrimer Networks”, Silicon Chemistry, 2003, 1.
    49. S. Rendon, W. R. Burghardt, A. New, R. A. Bubeck, and L. S. Thomas, “Effect of Complex Flow Kinematics on the Molecular Orientation Distribution in Injection Molding of Liquid Crystalline Copolyesters”, Polymer, 2004, 45, 5341 – 5352.
    50. R. A. Bubeck, P. R. Dvornic, J. Hu, A. Hexemer, X. Li, S. E. Keinath, and D. A. Fischer, “Near Edge X-ray Absorption Fine Strucutre (NEXAFS) Studies of Copper Ion-Containing PAMAMOS Dendrimer Networks”; Macromolecular Chemistry and Physics, 2005, 206, 1146 – 1153.
    51. R. A. Bubeck, L. S. Thomas, S. Rendon, W. R. Burghardt, A. Hexemer, D. A. Fischer, “Characterization of the Skin Orientation of Thermotropic Liquid-Crystalline Copolyester Moldings with Near-Edge X-Ray Absorption Fine Structure’, Journal of Applied Polymer Science, 2005, 98, 2473.
    52. S. Rendon, R. A. Bubeck, L. S. Thomas, W. R. Burghardt, A. Hexemer, and D. A. Fischer, “Interrogation of “Surface”, “Skin”, and “Core” Orientation in Thermotropic Liquid-Crystalline Copolyester Moldings by Near-Edge X-Ray Absorption Fine Structure and Wide-Angle X-ray Scattering.”  Journal of Applied Polymer Science, 2007, 106, 2502-2514.
    53. S. Rendon, W. R. Burghardt, R. A. Bubeck, “Orientation Dynamics in Commercial  Thermotropic Liquid, Crystalline Polymers in Transient Shear Flows”  Rheologica Acta, 2007, 46: 945-956.
    54. J. Fang, W.R. Burghardt and R.A. Bubeck. “In situ X-ray Scattering Measurements and Polydomain Simulations of Molecular Orientation Development during Injection Molding of Liquid Crystalline Polymers.” Proceedings of the XVth International Congress on Rheology, Monterey, CA, 2008, 1027: 39-41.
    55. J. Fang, W.R. Burghardt and R.A. Bubeck. “Polydomain Model Predictions of Molecular Orientation in Isothermal Channel Flows of Thermotropic Liquid Crystalline Polymers.” Polymer Engineering & Science, 2008, 48, 2258-2269.
    56. J. Fang, W.R. Burghardt and R.A. Bubeck. “An Apparatus for in situ X-ray Scattering Experiments during Polymer Injection Molding.” Review of Scientific Instruments, 2009, 80(4).
    57. J. Fang, W.R. Burghardt and R.A. Bubeck. “Bulk and Surface Molecular Orientation Distribution in Injection Molding of Thermotropic Liquid Crystalline Polymers: Simulation and Experiments.” Submitted to Polymer Engineering & Science (2009).

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